Tiger nuts are tubers that grow natively in several tropical areas. The foliage of the plants can resemble grass and the aggressive growth pattern of tiger nuts has led to their reputation as an invasive weed in some locations. The roots of the plants send out rhizomes that form small edible tubers. The tubers have a sweet, nutlike taste and are used in a traditional Spanish dish called horchata, or tiger nut milk. The production of tiger nuts takes place primarily in Spain, some South American countries and California, although it is possible to grow tiger nuts in a sufficiently sized planter in the home.
There are several names for tiger nuts, including chufa in Spain, tigernut sedge and earth almond. A handful of different varieties exist, as well, although most of them produce the same type of tuber from the root system. The plant itself forms flowers once it has matured, although these flowers require a very long and hot growing season to develop, so plants growing in cooler climate zones might not flower or have only small blooms.
When being cultivated for processing of the tubers, tiger nuts can benefit from not being fertilized or fed plant food. This is because they are particularly sensitive to the presence of nitrogen in the soil, which will spur an increased growth of the foliage while reducing the amount of tubers that are produced. Like many rhizomes, the tubers need a cool period of dormancy to grow again the next year. When properly dried, stored and kept free of moisture and molds, the nuts can last for a year or more and still have a good chance of germinating when planted.
In culinary applications, one of the main uses for tiger nuts is making tiger nut milk. This is a drink that is popular in Northern Africa and Spain, where it is called horchata. The milk is made by soaking the very hard tubers in water until many of the starches are removed, and then grinding them into a pulp. The pulp is soaked in water for several hours, after which sugar and vanilla might be added. After being chilled and strained, the milk is ready to drink.
Tiger nuts also can be used to create flour by being dried and ground, and cooking oil is made through a cold-press process. They also can be added to cosmetics, and used as bait when fishing. There are many beneficial minerals and vitamins in the tubers, including vitamins C and E, potassium and magnesium. The very robust growth cycle of the plants also has made them a potential crop for use in the production of biofuels.